1. Technical Field
The present disclosure generally relates to a structure for a semiconductor light source apparatus; more specifically, to a structure for a semiconductor light source apparatus that can measure a plurality of working parameters and adjust the light output accordingly.
2. Description of Related Art
Traditional light sources include fluorescent lamps, incandescent bulbs, light bulbs, and halide lamps. These traditional light sources have the disadvantages of high power consumption, large footprint, low stability, short user lifespan, and lowly coherent output light. Due to these disadvantages, traditional light sources are not adapted for using in many fields, such as digital electronics, optical communication technologies, flat panel display technologies, and biomedical engineering. However, with the advance of semiconductors, various semiconductor light sources have been gradually developed.
These semiconductor light sources include the light emitting diode and the laser diode. Generally speaking, these semiconductor light sources have some common advantages, such as low power consumption, low footprint, high stability, long user lifespan, and output light of high coherence and brightness, as well as output light of multiple wavelengths. Therefore, the semiconductor light source has become increasingly important. In addition, with the development of the blue semiconductor light source, white light can now be emitted by the semiconductor light sources. Hence, the semiconductor light source has slowly replaced the traditional light source in various applications.
Although the semiconductor laser has the above-mentioned advantages, there are still some limitations. One is an intrinsic property of the device, that is, the output power of the semiconductor light source decreases as the device temperature increases. Therefore, the detection of the device temperature of a working semiconductor light source has become an important technique. In conventional methods, device temperature measurement of the semiconductor light source is made by a temperature sensor outside the device. However, the most significant components of the detected temperature values include the outer casing temperature of the semiconductor light source, along with the environmental temperature surrounding the device. Hence, these temperature measurements do not correspond to the real device temperature.
U.S. Pat. No. 4,604,753 (abbreviated as Sawai hereinafter) disclosed a structure of a laser diode. In Sawai, a temperature sensing mechanism (1) and an automated temperature controller (ATC) are provided in the packaging of the laser diode. Thus the ATC can control the size of a working current based on the temperature of the laser diode, and therefore the ATC can stabilize the output power. Hence, the device disclosed in Sawai can effectively measure the device temperature of the laser diode and compensate the device according to the temperature measurements. However, in the fabrication of the device disclosed in Sawai, the electrical connections between the laser diode and the temperature sensor chip are made by wire bonding. The large internal resistance may affect the optical performance of device.